incrementally ingest eval results
nix-eval-jobs streams output, unlike hydra-eval-jobs. Now that we've
migrated, we can use this to:
1. Use less RAM by avoiding buffering a whole eval's worth of metadata
into a Perl string and an array of JSON objects.
2. Make evals latency a bit lower by allowing the queue runner to start
ingesting builds faster.
Also use the newly-restored constituents support in `nix-eval-jobs`
Note, we pass --workers and --max-memory-size to n-e-j
Lost in the h-e-j -> n-e-j migration, causing evaluation to always be
single threaded and limited to 4GiB RAM. Follow the config settings like
h-e-j used to do (via C++ code).
`nix-eval-jobs` should check `hydraJobs` and then `checks` with flakes
(cherry picked from commit 6d4ccff43c41adaf6e4b2b9bced7243bc2f6e97b)
(cherry picked from commit b0e9b4b2f99f9d8f5c4e780e89f955c394b5ced4)
(cherry picked from commit cdfc5c81e8037d3e4818a3e459d0804b2c157ea9)
(cherry picked from commit 4b107e6ff36bd89958fba36e0fe0340903e7cd13)
Co-Authored-By: Maximilian Bosch <maximilian@mbosch.me>
It seemed there was no self-contained end-to-end test actually doing
this?!
Among other things, this will help ensure that the switch-over to
`nix-eval-jobs` is correct.
Just ordering yourself after network-online.target will not guarantee
that it will be loaded. You'll have to either want or require it. Hence
the following trace on recent nixpkgs versions:
evaluation warning: hydra-queue-runner.service is ordered after 'network-online.target' but doesn't depend on it
* Update version in example
* Update docs to fix invalid indentifier when using 'hello'
* fix build issue for hello example
---------
Co-authored-by: Aaron Honeycutt <aaronhoneycutt@proton.me>
Original commit message:
> There are some known regressions regarding local testing setups - since
> everything was kinda half written with the expectation that build dir =
> source dir (which should not be true anymore). But everything builds and
> the test suite runs fine, after several hours spent debugging random
> crashes in libpqxx with MALLOC_PERTURB_...
I have not experienced regressions with local testing.
(cherry picked from commit 4b886d9c45cd2d7fe9b0a8dbc05c7318d46f615d)
When people reach out to the git repository they probably want to use
hydra from the same source.
This also removes the need for an overlay with simpler and more
performant direct use of the nixpkgs passed in. Before it was
re-importing nixpkgs.
test
There is an overlay for the `hydra` name, but `hydra_unstable` was used, which can refer to the nixpkgs package and lead to and outdated hydra version and requires configuring the correct package attribute downstream.
In my system logs I see this every time a new eval starts:
```
hydra-evaluator[PID]: hint: Using 'master' as the name for the initial branch. This default branch name
hydra-evaluator[PID]: hint: is subject to change. To configure the initial branch name to use in all
hydra-evaluator[PID]: hint: of your new repositories, which will suppress this warning, call:
hydra-evaluator[PID]: hint:
hydra-evaluator[PID]: hint: git config --global init.defaultBranch <name>
hydra-evaluator[PID]: hint:
hydra-evaluator[PID]: hint: Names commonly chosen instead of 'master' are 'main', 'trunk' and
hydra-evaluator[PID]: hint: 'development'. The just-created branch can be renamed via this command:
hydra-evaluator[PID]: hint:
hydra-evaluator[PID]: hint: git branch -m <name>
```
This ensures this hint is not logged anymore and unclutters the syslog.
I presume it does not really matter what name is chosen for the branch.
See https://github.com/NixOS/hydra/pull/1414#issuecomment-2412350929
The variable is defined in src/lib/Hydra/Helper/Nix.pm
Error message without this patch:
```
hydra-evaluator[PID]: Couldn't require Hydra::Plugin::S3Backup : Global symbol "$MACHINE_LOCAL_STORE" requires explicit package name (did you forget to declare "my $MACHINE_LOCAL_STORE"?) at /nix/store/xxx-hydra-0-unstable-2024-09-24/libexec/hydra/lib/Hydra/Plugin/S3Backup.pm line 95.
hydra-evaluator[PID]: Compilation failed in require at /nix/store/xxx-hydra-perl-deps/lib/perl5/site_perl/5.38.2/Module/Runtime.pm line 314.
hydra-evaluator[PID]: at /nix/store/xxx-hydra-perl-deps/lib/perl5/site_perl/5.38.2/Module/Pluggable.pm line 32.
```
